The main purpose of this study w as to prepare the losartan potassium controlled release floating tablets by using effervescerıt technique to extent the gastric residence time and enhance its bioavailability. The floating matrix tablets were prepared by using different proportion of polymers such as hydroxypropylmethylcellulose, karaya gum and sodium bicarbonate used as gas generating agent, by direct compression technique. Before compression the particulate matter of the series of formulations were evaluated for various micromeritic properties. The prepared floating tablets were evaluated for vveight uniformity, drug content uniformity, friability, hardness, floating characteristics such as floating lag time, total floating time, water uptake studies, compatibility studies of drug with polymers and in vitro drug release. The mathematical models were also used to investigate the principle release mechanism of drug release. The results showed that ali prepared floating tablet were have excellent swelling, floating capabilities with short floating lag time within 100 seconds and maintain controlled release up to 12 hours.

Keywords: Floating matrix tablet, Losartan potassium, Hpmc, Karaya gum.